Illustrated identification guide — PestControlBasics.com
🔍 Identification
Tiny: 2-3mm; tan to brown; large hind legs for jumping (resembles a tiny cicada or planthopper). Found in enormous numbers on south-facing windows, walls, and screens in September-October. Associated with hackberry trees (Celtis species) — if you have large hackberry trees nearby, this is almost certainly your pest. The distinctive nipple galls on hackberry leaves (round bumps on upper leaf surface) confirm hackberry psyllid activity on the tree.
🧬 Biology & Behavior
Hackberry psyllids complete their development inside the nipple galls they form on hackberry leaves. Adults emerge in fall and aggregate on warm surfaces (south-facing structures) seeking overwintering sites. They're attracted to lights at night. They jump when disturbed — which often causes them to be misidentified as fleas.
⚠️ Damage & Health Risk
Nuisance aggregation in structures; they can enter through window screens due to their small size; their jumping causes flea-confusion panic (they do NOT bite). No damage to structures or health risk.
🔧 DIY Treatment
Apply bifenthrin perimeter spray in September before aggregation peaks. Seal window screen gaps. Reduce exterior lighting. Once inside, vacuum to remove. The only true solution is removing nearby hackberry trees — which is rarely practical or advisable.
👷 When to Call a Pro
Rarely warranted — hackberry psyllid pressure is seasonal and self-limiting.